Mist-netting birds

Owlet Nightjar Aegotheles cristatus

I was out mist-netting birds last weekend at The Charcoal Tank Nature Reserve, New South Wales, on a trip organised by Mark Clayton. The aim is to catch a sample of birds several times a year as part of a long-term study of the changes in the numbers and species in the bird population. The nets were set the evening before and opened at first light, hence we caught this nocturnal bird, an Owlet Nightjar. This is the first I have seen caught in almost-daylight. Perhaps it had been feeding late because it was a cold night at the end of winter and there were few insects about.

Small, quiet, with big dark brown eyes, a long tail, and dark grey plumage
- all ideal for a nocturnal woodland bird

Owlet Nightjars are neither owls nor nightjars, they are classed in a family of their own, Aegothelidae. They roost by day in tree hollows and hunt at night, feeding on invertebrates, mostly insects, which they can catch in flight although they spend much time foraging on the ground. They are small dainty birds, only about 50g in weight, and they have a soft plumage similar to owls and frogmouths, for quiet flight.

Horsfield's Bronze-Cuckoo Chalcites basalis
  - the broad dark stripe over its ear coverts and the scalloped,
 buff tips to the wing coverts are diagnostic markings of the species. 

As the day opened up we heard four species of cuckoo calling: Pallid Cacomantis pallidus, Fan-tailed C. flabelliformis, Shining Bronze-Cuckoo Chalcites lucidus and this one, Horsfield's Bronze-cuckoo. We caught four of this last species and all were males, indicative of how male cuckoos, and many other species of birds, tend to migrate to their breeding grounds ahead of the females. The tail patterns, both topside and underneath, are diagnostic of the species' sex - the females have russet colouring on the outer tail feathers, the males, like this one, have black and white outer feathers.

     Top-side of Horsfield's Bronze-Cuckoo's tail     

    Underside of tail

We caught a good number of regular breeding birds of the area especially White-plumed Honeyeater Ptilotula penicillata and White-eared Honeyeaters Nesoptilotis leucotis for comparisons of biometrics. Our sample included a good mix of species; some resident, some returning to breed and some migrants passing through. There were examples of two races of Silvereye, Zosterops lateralis; the local Z.l. westernensis and the migrant Z.l. ochrochorous which breeds on King Island in the Bass Strait. We also caught fifteen Striated Pardalotes Pardalotus striatus at once in one net and there were three races in that flock; P.s. striatus which breeds in Tasmania, P.s. substriatus which breeds in the interior of the continent and P.s. ornatus which breeds in the south-east.

Z.l.ochrochrous

Z.l. westernensis 

                       

Z.l.w. Rufous flanks

Z.l.o. Tawny flanks

Z.l.w. Yellow throat

Z.l.o. White throat with yellow flecks

Perhaps, the most spectacular bird we caught was a male Brown Goshawk Accipiter fasciatus in full breeding plumage. Accipiters are aggressive and can inflict cuts with their bills and talons, so great care is necessary when handling them. This powerful predatory bird was such a contrast from the docile Owlet Nightjar we began the day with.

The talons are grasped firmly and the head held up away from our hands.
The whole bird is kept well away from our faces.

The bird had clean, slate-blue upper coverts and head. Its breast and underwing coverts were solidly barred.
All its flight feathers were complete, no moult.

The rounded tail is one of the better features to look out for if in doubt whether a bird seen is a
Brown Goshawk or a Collared Sparrowhawk Accipiter cirrocephalus, which has a square-ended tail.

The bright yellow eyes of an Accipiter - a determined hunter.

Note the heavy eyebrows, these shield the eyes, not only from sunshine, but against twigs and leaves when a goshawk crashes through thick vegetation in pursuit of its prey. The brows are unfeathered and the skin shows signs of abrasion. One of the honeyeaters we caught had a 4mm long thorn stuck in the skin on its crown, an example of what birds have to contend with when flying through woodland. I pulled the thorn out cleanly and the honeyeater flew off happily.

All the birds we caught flew off back into the bush. No animals were harmed in the making of this blog. 

Birds of Bowra

Crested bellbird

Following on from the previous two posts on my recent trip to Bowra wildlife sanctuary, run by the Australian Wildlife Conservancy, here is a brief outline of what birds we caught on the trip. I thank the AWC for their cooperation and Jon Coleman for organising the study, coordinating our visit with his team from Brisbane. Also, I thank the other members of our crew, Mark Clayton, Gil and Marion, and Richard Allen who was working not far from us most of the time and shared his knowledge of birds he and his son Mark caught.

A mist net set in the scrub

We set up about five nets each evening, ready to open at first light the next day. The habitats were mostly mallee and mulga, and although it had rained a week previously, the ground was dry and easily worked. It can be a no-go zone after heavy rain, due to vehicles becoming bogged.

Gil and Mark processing birds quietly at the banding table.

We caught 152 birds of 27 species in five days, the most numerous being Spiny-cheeked and White-plumed Honeyeaters, both common species of dry woodland habitats. It was a good trip with numerous birds that had been banded on previous visits re-trapped, which is what we need to establish some idea of the birds' movements within the reserve and their ages. Below is a sample of the birds found and caught by us this time around.

White-breasted Woodswallow - adult

There were three species of woodswallow regularly hawking over the treetop and picking food from the ground in open areas. These two and the Little Woodswallow, of which I saw several flying high, too high to get caught in the nets.

Black-faced Woodswallow - 1st year/juvenile

This Black-faced Woodswallow can be recognised as a young bird, fledged in the recent breeding season, by the buff-tipped coverts and feathers on the head. The adults have a smooth grey plumage.

Grey-headed Honeyeater - adult

We were lucky to hear, see and catch a few Grey-headed Honeyeaters. They are more abundant farther north and west, although they are a bird of the mulga woodland and that was the habitat we were in.

Red-backed Kingfisher - female

The Red-backed Kingfisher was a species that I never saw or heard until we caught one. They are usually easily found as they tend to call loud whistles from high tree-top perches. This is the kingfisher of the arid zone and dry open woodlands.

Australian Ringneck

Australian Ringnecks are common and widespread in the drier woodlands, especially the mallee and mulga. They could be found readily by following their loud calls, as parties of them fed on the bushes and trees.

Bourke's Parrot - adult female

The Bourke's Parrot is a parrot of the arid and semi-arid, mid interior country. They are generally a quiet bird and easily overlooked. The best time to find them was at dawn or dusk when they fly to drinking pools and roosts.

Hall's Babbler

The Hall's Babbler is a bird that is only found in south-west Queensland and north-west New South Wales. So was perhaps the most typical bird of the area we were in. The overall dark grey/brown plumage and the high breast-line distinguish the species from the similar White-browed Babbler which is found more widespread to the south and west. The other babbler in the area was the Chestnut-crowned Babbler, which we saw and was easily distinguished by its double white wing bars.

Variegated fairy-wren

Two common species, with wide ranges over arid and woodland areas were the Variegated and Splendid Fairy-wrens. As it was the end of the breeding season, the males of both species were moulting out of their bright blue breeding plumage into the duller grey/brown eclipse plumage they take on for the winter. They then look similar to the females and immature birds, although they retain their dark bill and the others have a red bill and eye-ring.

Splendid Fairy-wren

The Variegated Fairy-wren was a little further on with its moult than the Splendid Fairy-wren, but both will complete their change over a few weeks.

Variegated Fairy-wren

Close-up, the fairy-wrens looked especially blotchy with the flecks of blue feathers not yet moulted out.

Splendid Fairy-wren